MONDAY, Feb. 9 (HealthDay News) -- The use of inhalers containing corticosteroids to treat chronic obstructive pulmonary disease (COPD) might increase the risk of pneumonia by as much as 70 percent, researchers report.

Inhaled corticosteroids, used to treat asthma, are not approved for use in COPD patients. However, one product that is marketed by GlaxoSmithKline, Advair, combines steroids with a beta-antagonist and is approved to treat COPD. A similar product, Symbicort, marketed by AstraZeneca, is currently under consideration for use in COPD patients.

"It is not that we didn't know the potential for these risks, but these risks must be balanced against the uncertain benefits of the drugs providing some symptom relief in these patients," said lead researcher Dr. Sonal Singh, an assistant professor of internal medicine at Wake Forest University Baptist Medical Center.

No one should stop using their inhaler based on this study, Singh said. However, the inhalers are not effective for COPD, "and then you have these substantial risks," he said.

The report is published in the Feb. 9 issue of the Archives of Internal Medicine.

For the study, Singh's team reviewed the findings of 18 clinical trials that included a total of 16,996 people. The researchers looked for cases of pneumonia among people who were using inhaled corticosteroids for at least 24 weeks.

They compared them with people who had used a placebo, and they also compared those who had used a combination of inhaled corticosteroids and long-acting beta-antagonists with those who had used only the long-acting bronchodilator.

The researchers found that people taking corticosteroids alone or in combination with bronchodilators increased their risk of developing pneumonia by 60 to 70 percent. However, this increase in pneumonia was not associated with an increased risk of dying.

Singh noted that the finding means that about one in every 47 people with COPD who uses a corticosteroid inhaler for a year is likely to develop pneumonia linked to use of the drug.